Skip DBG_VALUE many places in live intervals and

register coalescing.  This fixes many crashes and
places where debug info affects codegen (when
dbg.value is lowered to machine instructions, which
it isn't yet in TOT).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95739 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 21 deletions

diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 27e5620..efc050e 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -512,6 +512,8 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
   baseIndex = baseIndex.getNextIndex();
   while (++mi != MBB->end()) {
 
+    if (mi->isDebugValue())
+      continue;
     if (getInstructionFromIndex(baseIndex) == 0)
       baseIndex = indexes_->getNextNonNullIndex(baseIndex);
 
@@ -527,8 +529,8 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
           end = baseIndex.getDefIndex();
         } else {
           // Another instruction redefines the register before it is ever read.
-          // Then the register is essentially dead at the instruction that defines
-          // it. Hence its interval is:
+          // Then the register is essentially dead at the instruction that
+          // defines it. Hence its interval is:
           // [defSlot(def), defSlot(def)+1)
           DEBUG(dbgs() << " dead");
           end = start.getStoreIndex();
@@ -606,26 +608,28 @@ void LiveIntervals::handleLiveInRegister(MachineBasicBlock *MBB,
 
   SlotIndex end = baseIndex;
   bool SeenDefUse = false;
-  
-  while (mi != MBB->end()) {
-    if (mi->killsRegister(interval.reg, tri_)) {
-      DEBUG(dbgs() << " killed");
-      end = baseIndex.getDefIndex();
-      SeenDefUse = true;
-      break;
-    } else if (mi->modifiesRegister(interval.reg, tri_)) {
-      // Another instruction redefines the register before it is ever read.
-      // Then the register is essentially dead at the instruction that defines
-      // it. Hence its interval is:
-      // [defSlot(def), defSlot(def)+1)
-      DEBUG(dbgs() << " dead");
-      end = start.getStoreIndex();
-      SeenDefUse = true;
-      break;
-    }
 
+  MachineBasicBlock::iterator E = MBB->end();  
+  while (mi != E) {
+    if (!mi->isDebugValue()) {
+      if (mi->killsRegister(interval.reg, tri_)) {
+        DEBUG(dbgs() << " killed");
+        end = baseIndex.getDefIndex();
+        SeenDefUse = true;
+        break;
+      } else if (mi->modifiesRegister(interval.reg, tri_)) {
+        // Another instruction redefines the register before it is ever read.
+        // Then the register is essentially dead at the instruction that defines
+        // it. Hence its interval is:
+        // [defSlot(def), defSlot(def)+1)
+        DEBUG(dbgs() << " dead");
+        end = start.getStoreIndex();
+        SeenDefUse = true;
+        break;
+      }
+    }
     ++mi;
-    if (mi != MBB->end()) {
+    if (mi != E && !mi->isDebugValue()) {
       baseIndex = indexes_->getNextNonNullIndex(baseIndex);
     }
   }
@@ -1056,7 +1060,7 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI,
       // If this is the rematerializable definition MI itself and
       // all of its uses are rematerialized, simply delete it.
       if (MI == ReMatOrigDefMI && CanDelete) {
-        DEBUG(dbgs() << "\t\t\t\tErasing re-materlizable def: "
+        DEBUG(dbgs() << "\t\t\t\tErasing re-materializable def: "
                      << MI << '\n');
         RemoveMachineInstrFromMaps(MI);
         vrm.RemoveMachineInstrFromMaps(MI);
@@ -1299,6 +1303,12 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
     MachineInstr *MI = &*ri;
     MachineOperand &O = ri.getOperand();
     ++ri;
+    if (MI->isDebugValue()) {
+      // Remove debug info for now.
+      O.setReg(0U);
+      DEBUG(dbgs() << "Removing debug info due to spill:" << "\t" << *MI);
+      continue;
+    }
     assert(!O.isImplicit() && "Spilling register that's used as implicit use?");
     SlotIndex index = getInstructionIndex(MI);
     if (index < start || index >= end)